Alpha 1,3galactosyltransferase: a target for in vivo genetic manipulation in xenotransplantation

This review discusses (1) evidence supporting the view that alpha 1,3galactosyltransferase, which is present in pig cells but is absent in human cells, is responsible for the rejection response by humans against pig tissue transplants, (2) studies on nucleotide sequences of the pig, mouse and cattle alpha 1,3galactosyltransferase gene and the alpha 1,3galactosyltransferase pseudogene in humans, (3) phylogenetic relationships between the alpha 1,3galactosyltransferase sequences of some non-human mammals and sequences for the human A transferase and the human alpha 1,3galactosyltransferase pseudogene, and (4) molecular methods of reducing the expression of the alpha 1,3galactosyltransferase epitope in pigs.